Chuck



June 7, 1932. GARNO 7 1,862,216

CHUCK Original FiledDec. 27, 1926 Geo rje EGarno as; I

Patented June 7, 1932 UNITED STATES PATENT or rcE GEORGE E. GARNO, OF VIORCESTER, MASSACHUSETTS, ASSIGNOR TO 7 THE HEATH) MACHINE COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MAS- SACHUSETTS 1 CHUCK Original application filed December 27, 1926, Serial No. 157,175. Patent No. 1,783,420. Divided and this application filed January27,1930. Serial No. 423,728. I

The invention relates to chucks of the collet type and provides an improved means for actuating the jaws, whereby their gripping surfaces will be always parallel to (or more strictly will contain lines parallel to) the axis of the chuck. The present application is a division from my prior and copending application Serial No. 157,175, filed December 27 1926, now Patent Number 1,7 83,- 420, granted Dec. 2, 1930.

In the standard type of collet chuck the jaws are made integral with a ring, and when the ring is drawn into the chuck, the jaws are forced together by a conical hood or other encircling body. In case the work varies by even a small amount from the size for which the particular jaws have been ground, the jaws will contact the work at an angle, and hold the workpiece with only a point or a line contact.

According to the present invention, the jaws are not rigid with the member to which the chuck draw bar is attached, but are pivotally connected thereto. In the modification illustrated in the present application and claimed herein this connection is made by two pivot pins and a link. Thus the jaws will always grip the workpiece solidly, and v not by point or line contact.

Another feature of the invention resides in the provision of interchangeable jaw pieces, all of which will fit the same set of jaws. The above and further advantageous features of the invention will hereinafter more fully appear, reference being had to the accompanying drawing, in which- Fig. 1 is a front view of a chuck or work holding device constructed in accordance with the invention.

Fig. 2 is a vertical sectional view taken on the line 2-2 of Fig. 1.

Like reference characters refer to like parts in the different figures.

Referring to both figures, the casing of the chuck comprises a plate 31, a hollow cylindrical member 32, and a generally cup shaped member 33. The plate 31 is attached to the hollow cylindrical member 32 by bolts 34, while the hollow member 32 is in turn at-, tached to the member 33 by the screws 35.

. opipeds.

The plate 31 has a threaded bore 36 by means of which it is attached to the threaded front end of a work rotating shaft or spindle 37. Said spindle is hollow for the reception of a chuck actuating rod or draw bar 38, by the longitudinal movement of which the chuck is opened or closed.

The chuck member 33 is slotted at 39, 39,

'39 (Fig. 1), said slots being desirably equally spaced around the circle, that is to say, 120

apart. The slots 39 are bridged by plates 40, 40, 40, which are fastened, by countersunk screws, to the outside surfaceof the member 33. Detachably fastened to the plates 40 are wedge members 41, 41, 41.

The front end of the rod 38 is screw threaded and has attached thereto a sleeve 42. The sleeve 42 provides a shoulder 43 and a short screw threaded portion 44, the latter being spaced from the shoulder 43 by acylindrical surface 45. A three armed member 46 fits .over the surface 45 and is held in place on the sleeve by a nut 47 which fits on the threaded portion 44, thesnut 47 being desirably provided with a locking screw 48. The

front end of the sleeve 42 is slidably received by a bushing 49 in the chuck member 33..

The wedge members 41 each have four inwardly extending projections 50, each of said projections being provided with plates 51. Plates 51 extend over the sides of the proj ections toward each other and form, together with the interior surface of the wedge members 41, guideways for three members 52,

which are substantially rectangular parallel- The members .52 are. each connected to ears 46' formed on the three armed member 46, the connections being made by links 53. The links 53 connect to themembers 52 by means of pivot pins 54, and to the ears 46 by means of pins-55. The ends of members 52are forked to receive the links.

When the rod 38 is moved to the right, Fig.

2, the chuck is opened, because the member 46, being in its farthest front position, the. jaw holding members 52 are at those ends of the guideways formed by the wedge members 41 and the plates 51 that are farthest apart. Conversely, movement of the draw bar to the left moves the members back in theinclined guideways. comparatively long jaw piece on said jaws positively in engagement with j 56 is attached to each member 52, and the the plane surfaces on the chuck to cause said ,lvheiiith'e jaw pieces'bohave ben properly chuck is therefore particularly adapted for jaws to move in a straight line, links pivotrelatively long workpieces. It must 7 be ally connected to said member mounted for understood, however, that the V chuck' is not axial movement and to said jaws, in order to thus limited in use, and a smaller'jaw piece drawsaid jaws inwardly of said chuck by may be used within the contemplationof the"'movement of said member, the links allowinvention.

The jaw pieces'56 fit in grooves-57 best lel relation to each other and to the elements shown in dotted lines in Fig. 2, on the inward of the surface of a workpiece;

side of members 52. They may be adjusted; In a chuck, a member slidably mounted longitudinally in said grooves by thumb in said chuck,'jaw members having opposite screws '58, which' are provided with coll'arparallel surfaces, inclined guide'waysiposi portions 59. U-shaped guide pieces" 60,"attively confining said jaw members and allowtached to and extending inwardly from the ing them to move only in a single line, and l.

members 52; surround the collars59 and thus links conne'cting"said first named slidable hold the screws 58 in position relative to said meinber to said jaw "members; -'whereby to members. It will be seen thatby turning the alloweleinents of the work holdin g jaws to screws 58, th'e jaw pieces 56 can be adjusted remain parallel as the jaws'ar e closed by tlre inwardly or outwardly of the chuck,"andas drawing' 'of said slidable member which they are moved inwardly, they will approach, the links, producesfmovemenrof the because of the inclined positionofmeinbers 52. jaw"members 'in the guides.

GEORGE GAR'NO; adjustedfor 'a given size of workpiece, they 7 are ffirmly clamped in position on the mem} bers] 52 by screws 6l, the'heads of which pro ject above long slo 'ts62 formed in members 52. For the purpose of getting at these screws 61, the members 41' likewisefprovide long slots 63 just above the slots 62. 2'

The chuck is provided with removable backing'plug's 64: which are adapted'to limit theinward movement of a workpiece; These plugs 6 l may be located in anyoiia setbf holes 65 "which are provided in "themember 33; in order that thenplugs may'be located 'in different positions for difie'rent sizes of workpieces. Itwill be understoodthatthedraw e5 fif th ja'ws, to maintain 'the'plaiie surfaces bar or: rod'38 is held to the left as cau se the chuck to clamp the workpiece a powerful spring',not shown, such as isfordinar ily' used in connection with draw barchucks.

V In the' appeiidje'ol'claimsfthe jawmembers 56 l and the parallelopipedal members "52 "will treated as a Si l perative element unless the claim itself specifies otherwise.

I claim: 7 I v l ln a chuck, a plurality of slid ably mounted jaw holding members,a plurality of slid ably'mounted on said members,-and

means to adjust saidjaws on' said members and means to lockthem in place thereon. 1

2. In a chuck, a' plurality of mounted jaw holding members, a plurality 0f jaws slidably mounted onsaid members, an'd'screwsto lock said jaws against niovelme'i'it on said members, although permitting slidingmovement of the'jaw hold ing' members. V i r i 3.111 a chuck, a member mounted for'axial movement therein, a set of work gripping jaws mounted for sliding'movenient infsaid 's riaf ing' elements of said jaws to remain in paral; V 

